Marble Cannon

Show us your pneumatic spud gun! Discuss pneumatic (compressed gas) powered potato guns and related accessories. Valve types, actuation, pipe, materials, fittings, compressors, safety, gas choices, and more.
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huse_spud
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Sun Jul 02, 2006 9:22 pm

the sprinkler valve, he could have put the sprinkler on top, made the stock shorter and the chamber and barrel a little longer.

this would be safer and he could still aim without having the sprinkler valve in his face (assuming he made the gun according his armspan).

and he could use a blowgun with hose and stick it where he needed it.

but its still a great gun, don't get me wrong. it's a powerhouse!

And btw professor it looks like he's wearing lipstick because of the lights, he prolly could use a little sunshine too so that his colors wouldn't contrast so much. :lol: kid, cut your hair too!

and there's your annual fashion announcement.
PVC Arsenal 17
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Mon Jul 03, 2006 3:38 pm

It would scare me to be holding that gun with that stock right by my face. And with one slight drop that thing will snap off and fck you up bad
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huse_spud
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Mon Jul 03, 2006 9:05 pm

ive cleared all other ideas out of my mind and am now focused on one project.

after brain storming, i am now planning to make a golf ball piston shotgun that's will be similiar to this gun but improve upon the idea.

and OwThatsMyEye don't be offended by our suggestions i was pretty pissed off when people started critisizing what i call my "DWV launcher" :lol: , but now i know they were just trying to help.
accept this as a learning experience.
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noname
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Mon Jul 03, 2006 9:30 pm

For a golf ball shotgun I'd use 2" SCH 40 for a good spread, not big, but not that small either.
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huse_spud
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Mon Jul 03, 2006 9:57 pm

noname wrote:For a golf ball shotgun I'd use 2" SCH 40 for a good spread, not big, but not that small either.
i'm gonna do that 2" to 2" sleeving trick.
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noname
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Mon Jul 03, 2006 10:24 pm

Oh god that's a pain in the butt, take it from me. And then it is too good of a fit; they won't spread out all over.
OwThatsMyEye
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Mon Jul 03, 2006 11:15 pm

PVC Arsenal 17 wrote:I'm wondering why you didn't put the sprinkler valve before the stock so you don't have to vent all that air. That way the stock is unpressurized and even safer to use. All that air inside it now is not contributing to the gun's power.
the main reason is it is more compact this way. and acually the whole stock isn't presherized I took some 1/2" plugs and sanded them down to fit the 3/4" pipe then put them in on the other sides of the tees that conect the stock to the gun.
If you are confused this may help to ilistrate it.
http://share.ws/img/4c74751049098f2e65e ... 8b/pic.bmp
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noname
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Tue Jul 04, 2006 11:49 am

Yeah that would work. I should probably do that sometime considering all my guns with stocks are pressurized except my coax.
PVC Arsenal 17
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Tue Jul 04, 2006 3:50 pm

Hey noname, I liked your design on your extreme coaxial. I might build it to shoot 12 grams. hope you dont mind!
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noname
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Wed Jul 05, 2006 10:00 am

Why would I? Although 12 grams might lose a lot of air trying to seal the diaphragm.
PVC Arsenal 17
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Wed Jul 05, 2006 3:12 pm

why is that?

It sounded perfect to me... fill up with a 12 gram and then shoot it the next shot!
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noname
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Wed Jul 05, 2006 6:17 pm

You have to get some air into the gun behind the diaphragm to get it to seal. It would work but you would probably lose about 10% of the CO2
PVC Arsenal 17
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Wed Jul 05, 2006 7:49 pm

If I used a fixed flexing diaphragm it wouldn't. Is yours a floating diaphragm or does it have a spring?


what is the perfect fit for 12 grams? 3/4 is close but a bit big.
OwThatsMyEye
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Wed Jul 05, 2006 8:31 pm

PVC Arsenal 17 wrote:If I used a fixed flexing diaphragm it wouldn't. Is yours a floating diaphragm or does it have a spring?


what is the perfect fit for 12 grams? 3/4 is close but a bit big.
i cant really figure out what u guys are talking about but 3/4" copper fits co2's pritty well.
PVC Arsenal 17
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Wed Jul 05, 2006 8:45 pm

Is it a better fit than 3/4 pvc? I might try it thanks.

we were talking about the diaphragm which is the valve that seals the barrel until the back of the gun is vented.

If you have a floating diaphragm, it seals by pushing against the barrel when air is put into the chamber from behind it at a fast rate.

A spring diaphragm is the same setup but uses a spring to help it seal so you don't waste air pressure to move it.

A fixed diaphragm is a sheet of rubber or neoprene that always seals against the barrel and just flexes in and out.
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